The invention concerns a process for driving a rigid body which, for producing tumbling movements in gimbal suspensions is displaceable about two mutually spaced axes directed in different directions and which is drivable by a drive means and a transmission between the drive means and the gimbal suspensions, whereby the body performs a non-uniform rotary movement with periodic wobbles during the tumbling movement.
The body serves particularly as a hollow body for receiving goods to be processed which are to be subjected to physical or chemical processes, whereby because of the simultaneous tumbling and rotary movements particularly favourable effects are achieved with regard to the course of such processes.
During simultaneous tumbling and rotary movements of a hollow body more or less filled with goods to be treated, inertial forces arise which do not permit the drive to be achieved by means of simple transmission means. Additionally, when the body rotates around two mutually spaced skew axes, in the mutually oppositely rotating driving elements carrying the gimbal suspensions differing angular velocities arise which are exerted in a periodically alternating manner from the side of the body on these driving elements because of the kinematics of the arrangement, which may be regarded as a swivel-joint. For these reasons it is not advisable to utilise positively connected transmission means for driving the body. Since however, on the other hand, the effects of spatial three-dimensionally directed longitudinal and rotary movements arising through the suspension of the body on the goods to be processed in the body have proved to be particularly favourable in relation to the course of physical and chemical processes, and the achievement of homogeneous mixtures, etc., the task is to provide a drive with which the above-mentioned problems may be solved and in which the non-uniformities of motion due to the kinematics and the inertial forces are compensated or balanced to such an extent that sufficiently high r.p.m. is achievable to satisfy the economic installation of such machine. Furthermore it is important to provide a construction of the machine which makes it possible for the material to be processed within the body to be subjected to the specific process in a continuous process rather than in a batch-wise manner.
To solve the above-mentioned tasks, the process described above is characterised according to the invention in that in order to balance torque fluctuations caused by the difference in angular velocities at the driving side and driven side of the transmission and by inertial forces, torque is periodically alternatingly stored in torque-transmitting members of the said transmission and returned to the latter. In this way suitable transmission forces caused by excess of torque are passed into a resiliently yielding energy store and during periods of shortfall, the stored energy or forces are passed back from the energy stores into the transmission. During periods of an excess of torque, an oppositely directed torque is produced and passed back into the transmission, and on the other hand during periods of torque shortfall, an additional equidirectional torque is produced and passed back into the transmission. Finally, in an expedient manner, periodically torque may be removed from the transmission, stored and then passed back into the transmission.
The invention also concerns apparatus for carrying out the process. The apparatus comprises a body which, for producing tumbling movements in gimbal suspensions, is displaceable about two mutually spaced axes directed in different directions and which includes a drive means as well as transmission means between the drive means and rotatably journalled shafts with which latter a respective one of the gimbal suspensions for the body is connected. The apparatus is according to the invention characterised in that the transmission means include torque transmitting members one of which is operatively connected with the drive means and another of which is operatively connected with a shaft carrying the gimbal suspension and that resiliently yielding energy stores are arranged between the torque-transmitting members for the periodical alternating storing and releasing of forces (energy). Preferably, the torque-transmitting members include two mutually coaxially arranged discs of a shaft coupling, the end surfaces of the discs facing each other being provided with annular recesses which together form a closed annular channel in which are arranged rolling elements and the energy stores in the form of coil compression springs arranged alternatingly and successively with the rolling elements in the circumferential direction, and that at least one abutment is arranged at each of the discs which abutment project(s) into the annular channel and form(s) a support for the energy stores. Both of the discs constituting the torque-transmitting members may be arranged on one shaft with which the disc on the driven side is connected rigidly for rotation, while the disc on the driving side is connected rigidly for rotation with a driving wheel, for example a gear wheel or a sprocket wheel, and the disc on the driving side and the driving wheel are arranged on the shaft so as to be rotatable relative thereto.
In this way the two discs may rotate relative to each other about a predetermined angle whereby the energy stores in the form of coil compression springs are pressed together when a torque excess arises so as to store torque in this way, which then during a succeeding period of torque shortfall may be released again.
Expediently, the transmission means for each of the shafts connected with the gimbal suspension are formed identically with each other and the drive of the two shafts through which or by means of which rotation of the body in a tumbling and rotary movement is carried out ensues so that the discs on the driving side are coupled to a respective shaft carrying a respective gimbal suspension via a non-slip movement transmission, for instance in such a way that both driving side discs are peripherally toothed. Then, the energy stores in the form of coil compression springs, together with the rolling elements between the individual springs, are arranged on the two shafts respectively between one of the driving-side discs and one of the driven-side discs.
As an additional measure, periodically torque may be removed from the transmission, stored and then passed back into the transmission.
To this end, a cam disc is in operative connection with at least one of these shafts, preferably with both shafts, the peripheral surface of each disc having sections with differing radial spacing from the axis of rotation, wherein sections with greater and smaller spacing alternate successively in a peripheral direction, and that the peripheral surface of each cam disc co-operates with a further energy store, for example also in the form of a coil compression spring, which energy store is stationarily supported in the frame of the machine and exerts a pressure force against the peripheral surface of the cam disc whereby torque is exerted via the cam disc on the shafts. Expediently, the spring does not press directly against the cam disc but rather against a pivotally journalled lever with a rolling element journalled at the end of the lever which rolls on the peripheral surface of the cam disc. With the aid of this additional energy store, the degree of uniformity of the movement of the rotating body may be significantly increased.
Other means may also be used as energy stores, and particularly the storage of mechanical, hydraulic, pneumatic, magnetic, electrodynamic and other storable forces come into reckoning. However, in the preferred embodiment of compression springs arranged between the discs of a shaft coupling the advantage arises that the discs also have the function or role of inertial masses or may be integrated with such masses, while in any other constructional solution, additional space would be required for a flywheel. Furthermore, as an additional advantage, the shafts carrying the discs may be formed as hollow shafts so that the goods being processed may be passed through the hollow shafts into the interior of the body in a continuous process and then passed back from there.
The body carrying out tumbling and rotary movements serves not only for the already mentioned performing of physical or chemical processes on the goods to be processed contained in its hollow interior, but rather it displays its particular effects also on goods to be processed surrounding the body and is in this way suitable for very many cases of application.
Other advantages and details of the invention will become clear from the following description and drawings, which illustrate a preferred embodiment of the invention.